Curved sectional mandrel



(ModeL) T. GONNERS. GURVED SEGTIONAL MANDREL. N0. 553,608. Patented Jan. 28, 1896.

UNITED STATES PATENT ()EEIcE.

TIMOTHY CONNERS, OF BROOKLYN, NEW YORK.

CURVED SECTIONAL MANDREL.

SPECIFICATION forming part of Letters Patent No. 553,608, dated January 28, 1896.

I Application filed September 27, 1894. Serial No. 524,217. (Model) To aZZ whom it may concern.-

Be it known that I, TIMOTHY CONNERS, a citizen of the United States, and a resident of Brooklyn, in the county of Kings and State of New York, have invented a new and useful Improvement in Curved Sectional Mandrels, of which the following is a specification.

My invention relates to curved sectional mandrels especially adapted for use in finishing the seams of curved sheet-metal tubes. The seam of such a tube when taken from the forming-dies is left in the form of a ridge on the outside of the tube and generally running in the plane of its curve or curves, and it has heretofore been customary to insert into the tube a separate mandrel for each curve, each mandrel adapted to bear firmly beneath its portion of the seam in order that the seam might be bent over and finished by means of a pressure device applied on the outside of the tube and above the mandrel. It will be seen, therefore, that the seam could not be finished at one application of the pressure'device, because the several mandrels must be separately inserted, and thus considerable time was required in finishing the seam. In order to accomplish the desirable result of finishing the seam at one application of the pressure device, it has been long sought to provide a mandrel adapted to be freely inserted within the curved tube and freely withdrawn therefrom, and which could at the same time present to the under side of the seam a continuous unbroken surface over which the pressure device might operate without denting or injuring the tube or the seam. By my invention, so far as I am aware, the first mandrel is offered by which these desired results may be attained.

The invention consists in a curved sectional mandrel, the sections of which are so connected together as to be capable of independent movement one of another, but when fitted closely together the body-surface on one or both sides of the combined several sections will be continuous and unbroken along the plane of the curve or curves of the mandrel.

In the drawings I have illustrated one embodiment of my invention, the mandrel be ing formed to fit a curved tapering tube circular in cross-section, and of such form as is generally used in spouts for teapots. This particular form, however, is, of course, not an essential part of the invention.

Figure 1 is a side elevation of a tube in which the mandrel is fitted. Fig. 2 is a longitudinal sectional view of the mandrel. Fig. 3 is a side elevation of the mandrel extended. Fig. 4 is a longitudinal sectional view of two of the sections taken at right angles to the section plane of Fig. 2.

The mandrel A comprises the sections a, b, c and (Z so formed that when their abutting ends are fitted closely together the surface of the mandrel will be continuous and unbroken not only along the plane of its curves, but also the entire lateral surface, or the surface which comes in contact with the interior of the tube will be continuous and unbroken, so as to entirely fill the tube. These sections are fastened together, so as to make the mandrel flexible, by any suitable means, which may, as shown in the drawings, consist of slotted links 6 working in sockets or recesses in the several sections and held in place by the pin s f. The slots in the links give extensibility to the sections, as shown in Figs. 2, 3 and 4, as well as flexibility. The object of the extensibility being to permit the several sections to separate one from another, and thus provide for tions cannot twist or rotate with respect to one another, as shown. This prevents the sections from getting twisted when being inserted into or withdrawn from a curved tube, and enables them to be easily removed without being caught by the curves of the tube. The means for connecting the sections of the mandrel flexibly and even extensibly together, however, so as to provide an unbroken surface when the sections are fitted closely together, maybe considerably varied, as will be apparent to a skilled mechanic, without departing from the spirit of my invention, and I do not therefore wish to be limited to the particular means shown, although I prefer the means shown.

The mandrel is provided with a handle B by which it maybe thrust into and withdrawn ioo from the tube 0. This tube is made of two longitudinal sections-united by the seams g g, which require to be turned down before they are finished. To accomplish this result the mandrel A, which, when its sections are fitted together, conforms to the interior of the tube, is thrust into the tube and the seam pressed down by any suitable pressure device. The body-surface of the mandrel being unbroken and continuous beneath the seams when pushed in place, there will be an even support for the pressure device, and hence no flaw or imperfection in the seam. One operator can completely finish both seams in a moment. Thus not only is there a great saving in time, but the seams finished on my mandrel will be more even and uniform than those heretofore made.

It is of course obvious that the mandrel may be polygonal, oval or any other shape in cross-section, as well as circular, and different portions of its length may have different shapes in cross-section according to the shape of the tube to be operated upon.

Of course it is evident that to finish a tube having but one seam a mandrel might be employed comprising a plurality of sections flexibly and extensibly united and having a smooth unbroken body-surface only on that side of the mandrel coming underneath the seam. Moreover, in finishing a tube having two seams on opposite sides a mandrel might be employed comprising a plurality of sections flexibly and extensibly united and having a smooth unbroken surface on one side only for finishing one of the seams, and another such mandrel might be employed with a continuous unbroken surface on the opposite side for finishing the other seam. If two such mandrels were employed to finish a tube having two seams, of course the full advan 1. A curved mandrel comprising a plurality of sections flexibly united, and having continuous, unbroken body surfaces on opposite sides of the mandrel along the plane of the curve or curves when the sections are fitted together, so arranged as to be capable of insertion within and withdrawal from a hollow tube substantially as set forth.

2. A curved mandrel comprising a plurality of sections flexibly and extensibly united, and having a continuous, unbroken body surface along the plane of its curve or curves when the sections are fitted together, so arranged as to be capable of insertion within and withdrawal from a hollow tube substantiall y as set fortln 3. A curved mandrel comprising a plurality of sections flexibly and extensibly united and so as to prevent rotation with respect to one another, and having a continuous body surface along the plane of its curve or curves when the sections are fitted together, so arranged as to be capable of insertion within and withdrawal from a hollow tube substantially as set forth.

4. A curved mandrel comprising a plurality of sections flexibly and extensibly united by means of slotted links, and having a continuous and unbroken body surface along the plane of its curve or curves when the sections are fitted together, substantially as set forth.

5. A curved mandrel comprising a plurality of sections flexibly and extensibly united by means of slotted links pivoted in recesses in the abutting ends of the sections, and having a continuous and unbroken body surface TIMOTHY CONNERS.

\Vitnesses DANIEL BROPHY, IIEZEKIAH GARRIS. 

